1. Field of the Invention
The present invention relates to a communication system, a communication device, a program and a communication control method.
2. Description of the Related Art
Discussions have been taking place recently regarding secondary usage of a spectrum assigned for primary usage to provide a secondary communication service depending on the use condition of the spectrum. For example, the standard specification for allowing an unused channel contained in a spectrum of the U.S. digital TV broadcast (TV white spaces) to be available for radio communication has been studied in the IEEE802.22 working group (“IEEE802.22 WG on WRANs”, [online], [Searched on Jan. 5, 2009], cf. Internet <URL:http://www.ieee802.org/22/>). Further, according to the report from the Federal Communications Commission (FCC) on November 2008, the discussions are directed toward permitting secondary usage of TV white spaces by using specific communication devices that have been authorized by fulfilling a certain criterion (“Second Report and Order and Memorandum Opinion and Order”, [online], [Searched on Jan. 5, 2009], cf. Internet <URL:http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-08-260A1.pdf>). In addition, there are moves, led by the EU, afoot to universally allocate a dedicated control channel called the cognitive pilot channel (CPC) for making dynamic spectrum access (DSA). Technological studies for a secondary usage system that makes DSA are also being progressed in IEEE Standards Coordinating Committee (SCC) 41.